News Group problem..please help!!

There is a group of 30 people who communicate only by phone. During any one to one phone conversation the two members exchange all their information. Find the number of calls needed so that everyone finds out every bit of news.

There is a group of 30 people who communicate only by phone. During any one to one phone conversation the two members exchange all their information. Find the number of calls needed so that everyone finds out every bit of news.

Thanks for any help you can give me!!

Interesting.

I recommend starting with smaller networks first to try to get a handle. For example, with four people, you can think of four binary numbers between 0000 and 1111 representing the state of each person's knowledge, and the following scenario can happen